Based on computational fluid dynamics/infrared radiation (CFD/IR) numerical calculations

the effects of different structures and nozzle pressure ratio (NPR) on the aerodynamic and infrared radiation characteristics were revealed for a single expansion ramp nozzle (SERN).The results show that:with increase of ramp angle

the thrust-vector angle is enlarged and axial thrust coefficient is decreased rapidly;with increase of nozzle pressure ratio

the axial thrust coefficient increases firstly and then decreases

meantime

the thrust-vector angle reduces;as the length of sidewall increases

axial thrust coefficient improves slightly.The ramp of nozzle can significantly shield the infrared radiation of plume and inner-wall of nozzle.The radiation detected from underside of nozzle is only 10% of that from upside of nozzle.With increase of nozzle pressure ratio

the infrared radiation from underside of nozzle is reduced.